The police will not likely seek you out over this warrant, but if stopped by the police for some other reason and a warrant check is run, you will be taken into custody. You should not stay in the wind too long; go into the court that issued the warrant, preferably with a lawyer, and let the clerk's office know you want to remove the warrant. It would help if you had the money to pay the outstanding fines with you when you go in. The fact that the letter was sent to your former address in no way invalidates the warrant, but it may cause the judge to not assess the $50 warrant removal fee, as you can argue that any notice you were sent to appear on the 29th was sent to the wrong address. On the other hand, if you are on probation, you are required to report any change of address to your probation officer, so if you failed to report a change of address, you do not want to draw attention to this additional probation violation in order to save $50. Depending on what you are on probation for, your record and your history of violations, your PO may or may not request that you be held in custody without bail, pending a final surrender hearing.
Dominic Pang (617-538-1127)
Since the court doesn't know why you didn't appear, it probably found you in default, though it is hard to tell from the information you provided. If you ignore it, you may be arrested. Therefore, you should contact the court, tell them what happened and the clerk will tell you the next step, probably to come to court and clear up the issue.
However, you also face a potential problem in that most probation terms require that you keep the probation department apprised of your location, so this might raise the stakes for you.
If a term of probation was paying a fine, you might be able to defend the charge on the grounds that you were unable to pay it despite your best efforts. If this is your defense, you must be prepared to show what efforts you made to get the assets to pay the fine and to show why you were unsuccessful.
These complications mean that you should contact a competant and experienced criminal defense attorney immediately so that you can deal with the default before you are arrested.
Evaluating any legal question requires a detailed knowledge of the specific facts involved. Since a short question will rarely contain all the relevant facts, the answer here should be considered a general comment for your consideration and not legal advice.
From what you wrote, it appears as if you missed a scheduled court appearance (and/or a payment date). As a result of your failure to appear, the Court issued a warrant.
You need to go to Cout and remove that default. Otherwise, the warrant will remain and you will be arrested at some point. You may want to consult with counsel first about the particulars of the case to understand exactly what will happen when you arrive and what you can do to help your situation (prior to arrival and while there).
It is unlikely that they are out looking for you, but if you are stopped for a driving infraction or otherwise come in contact with the police, they can arrest you if there is a warrant. It is better to show up in court voluntarily than through the lock-up.